In industrial process control environments, it is often necessary for a piece of process control equipment located along the process equipment and/or piping to meet certain minimum performance characteristics to ensure that the piece of control equipment is operating in accordance with minimum operational standards. By way of example, such process control environments may include industrial processing, mining, manufacturing, petrochemical extraction, transportation, and refining, energy production facilities, and the like. An individual piece of process control equipment is often referred to as a “field device.” Some typical exemplary field devices include sensors, switches, valve controllers, and/or valves. These minimum performance characteristics and minimum operational standards generally are intended to ensure that the process control environment meets some given applicable standards for performance and/or safety.
It is often necessary to provide information relative to these performance characteristics and/or operational standards directly on or immediately associated with the field device so as to be visible to a person when in the process control environment. Such information often includes, for example, safety certification information and/or other information specific to that particular field device.
To associate the safety or certification information with a field device, it is common to fix the information onto a nameplate, such as a metal tag. The nameplate is then secured directly onto the field device. For example, for a proximity sensor switch rated for use in an environment where functionality must be ensured under possible explosive conditions, the certification information would be written or stamped on a metal tag. The tag would be secured directly to the outside of a housing for the proximity sensor switch with glue or rivets so as to be visible during use in the process control environment. Alternatively, the certification information could be written directly on the housing.
Although this method of associating certification information is suitable for a field device that can function in only one specific manner, the conventional approach is not convenient or suitable for a field device that can be configured to be used in different manners having different certification requirements. For example, on a configurable process control device, such as a proximity sensor switch that is adapted to be configured to emulate more than one type of switch, the nameplate would need to be changed to display the appropriate certification information every time the proximity sensor is configured or reconfigured to emulate a different type of switch. This can be both costly and inconvenient for the user. Consequently, there is a need for an improved system of displaying information about a configurable process control device on or immediately associated with the device.